#include <stdio.h>
#include <stdlib.h>
/*
transform from string to int
*/
int parseInt(char * str){
	int result=0;
	char * p=str;
	while(*p!='\0'){
		if(*p>'0' &&*p<'9'){
			result=result*10+*p++-'0';
		}else{
			printf("the String has no number char!\n");
			exit(1);
		}
	}
	return result;
}
